I suspect most people here are familiar with the late Al Hirschfield’s habit of hiding his daughter Nina’s name in his drawings.

More recently I have observed the use of ‘Nina’ at crossword fora to refer to various hidden messages in crossword puzzles, either cryptic or normal, such as a message spelt out in the perimetrical letters or the pun found in the first two across entries in the normal crossword in The Independent. It’s a bit difficult to find out when this started, though, or whether there are any other extended uses for the word. Does anyone know anything about this?